Turbine blade with a cover plate and a protective layer applied to the cover plate

A turbine blade for a steam turbine, comprising:

• a cover plate integrally formed onto a blade leaf of the blade;
• and
• a protective layer that consists of an alternative material applied to a surface of the cover plate that faces away from the blade leaf, where the protective layer is formed by a cobalt based armor alloy comprising:
• a maximum of 3% nickel,
• a maximum of 3% iron,
• approximately 1.1% to 1.2% carbon,
• approximately 28% chrome,
• approximately 1.0% to 1.1% manganese,
• approximately 1.0% to 1.1% silicon, and
• 4.5% tungsten.

A steam turbine, comprising:

• a rotationally supported turbine shaft;
• and
• a plurality of turbine blades arranged on the shaft where the blades are arranged to form a plurality of blade rows, wherein each blade comprise:
• a cover plate integrally formed onto a blade leaf of the blade;
• and
• a protective layer that consists of an alternative material applied to a surface of the cover plate that faces away from the blade leaf, where the protective layer is formed by a cobalt based armor alloy comprising:
• a maximum of 3% nickel,
• a maximum of 3% iron,
• approximately 1.1% to 1.2% carbon,
• approximately 28% chrome,
• approximately 1.0% to 1.1% manganese,
• approximately 1.0% to 1.1% silicon, and
• 4.5% tungsten.

A method for producing a steam turbine with a plurality of turbine blades, comprising:

• providing a rotationally supported turbine shaft;
• and
• arranging a plurality of turbine blades on the shaft where the blades form a plurality of blade rows and each blade comprises:
• a cover plate integrally formed onto a blade leaf of the blade;
• and
• a protective layer that consists of an alternative material applied to a surface of the cover plate that faces away from the blade leaf, where the protective layer is formed by a cobalt based armor alloy comprising:
• a maximum of 3% nickel,
• a maximum of 3% iron,
• approximately 1.1% to 1.2% carbon,
• approximately 28% chrome,
• approximately 1.0% to 1.1% manganese,
• approximately 1.0% to 1.1% silicon, and
• 4.5% tungsten, and
• where the cover plates of the turbine blades form a continuous shroud, the protective layer being applied to the shroud only after the mounting of the turbine blades on the turbine shaft.